Healthy people, ages 50 to 69, drank a mixture high in antioxidants called cocoa flavanols for three months. And they performed better on a memory test than people who drank a low-flavanol mixture.

On average, they performed like people two to three decades younger on the memory task. They performed about 25 percent better than the low-flavanol group.

But you should remember that sugar hurt your memory. Thus you shouldn’t eat a lot of white chocolate but dark chocoalte.

Brickman A, Khan U, Provenzano F, Yeung L, Suzuki W2, Schroeter H3, Wall M4, Sloan RP4, Small SA5; “Enhancing dentate gyrus function with dietary flavanols improves cognition in older adults.; Nat Neurosci. 2014 Dec;17(12):1798-803.